Implantable medical devices may be implanted in a patient to perform a therapeutic function for that patient. Non-limiting examples of such devices include pace makers, access ports (such as vascular access ports, infusion ports, and ports used with gastric band systems, etc.) and gastric pacing devices. Such implants may need to be attached, perhaps subcutaneously, in an appropriate place in order to function properly. It may be desirable that the procedure to implant such devices be quick, easy and efficient.
Ports may be placed beneath the skin of a body for injecting fluids into or withdrawing fluids from the body. By way of example, vascular access ports may be used for infusing medication, blood draws, and many other applications. Injection ports may be used for adding or withdrawing fluid in adjustable gastric band systems. These various access ports may include an implantable port housing coupled to a fluid conduit which delivers fluid to or withdraws fluid from a location in the patient's body (e.g., a vein or a gastric band, etc.).
Gastric band systems are operable to restrict the flow of food from the esophagus into the stomach. Some gastric bands include a fluid-filled elastomeric bladder with fixed endpoints that encircles the stomach just inferior to the gastro-esophageal junction. When fluid is added to the bladder, the band expands against the stomach, creating a food intake restriction or stoma in the stomach. To decrease this restriction, fluid is removed from the bladder. Examples of gastric bands are disclosed in U.S. Pat. No. 7,367,937, entitled “Gastric Band,” issued May 6, 2008, the disclosure of which is incorporated by reference herein; U.S. Pat. No. 7,416,528, entitled “Latching Device for Gastric Band,” issued Aug. 26, 2008, the disclosure of which is incorporated by reference herein; and in U.S. Pat. No. 6,067,991, entitled “Mechanical Food Intake Restriction Device,” issued May 30, 2000, the disclosure of which is incorporated by reference herein.
To the extent that an adjustable gastric band system includes an injection port configured to receive the needle of a syringe assembly in order to add or withdraw fluid to or from the gastric band, those of ordinary skill in the art will appreciate that it may be desirable in some settings to locate both the injection port and, more specifically, the center of the injection port (e.g., when the septum of the injection port is at the center of the injection port). Locating the approximate center of the injection port with some degree of accuracy may facilitate addition or withdrawal of fluid via the injection port to adjust the gastric band system. One example of a system and method for identifying the location of an injection port is disclosed in U.S. Pub. No. 2006/0211914, entitled “System and Method for Determining Implanted Device Positioning and Obtaining Pressure Data” published Sep. 21, 2006, and issued Aug. 17, 2010 as U.S. Pat. No. 7,775,215, the disclosure of which is incorporated by reference herein.
Those of ordinary skill in the art will appreciate that it may be advantageous in certain circumstances to sense pressure, strain, and/or other parameters associated with operation of a gastric band device. In some settings, it may be desirable to obtain data indicative of the pressure of fluid in a gastric band. Various examples of methods and devices for obtaining pressure data and other types of data are disclosed in U.S. Pub. No. 2006/0189888, entitled “Device for Non-Invasive Measurement of Fluid Pressure in an Adjustable Restriction Device,” published Aug. 24, 2006, and issued Apr. 20, 2010 as U.S. Pat. No. 7,699,770, the disclosure of which is incorporated by reference herein. Additional examples of methods and devices for obtaining pressure data and other types of data are disclosed in U.S. Pub. No. 2006/0199997, entitled “Monitoring of a Food Intake Restriction Device,” published Sep. 7, 2006, and issued Sep. 13, 2011 as U.S. Pat. No. 8,016,745, the disclosure of which is incorporated by reference herein. Such parameter data may be obtained before, during, and/or after adjustment of a gastric band, and may be useful for adjustment, diagnostic, monitoring, or other purposes, and may also be obtained with respect to a mechanically actuated gastric band. In settings where a fluid-filled gastric band is used, pressure data may be used to determine whether the amount of fluid in the gastric band needs to be adjusted; and/or for other purposes.
While a variety of implantable access ports and gastric band systems have been made and used, it is believed that no one prior to the inventor(s) has made or used an invention as described herein.
The drawings are not intended to be limiting in any way, and it is contemplated that various embodiments of the invention may be carried out in a variety of other ways, including those not necessarily depicted in the drawings. The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, and together with the description serve to explain the principles of the invention; it being understood, however, that this invention is not limited to the precise arrangements shown.